Auto routing and/or defining routes

What do you think about me mixing defined routes with auto routing? Is that generally a problem? I thought CI would check for an existing controller in a given directory and – if that does not exist – then reads the matching route defined in Routes.php. Am I making a mistake in my thinking here?

You misunderstand CI routing.
It checks defined routes first, and if not found, find the controller by auto routing (if it is enabled).

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